Bug 16184 - Report bor_issues_top shows incorrect number of rows

 Bug 16184 - Report bor_issues_top shows incorrect number of rows

TEST PLAN
---------
1) Have at least 6 patrons with checkouts and some checkins.
2) Reports -> Patrons with the most checkouts
3) Click 'Submit' (default is 5)
   -- more than 5 entries listed.
4) Apply patch
5) Refresh page
   -- only 5 entries listed.
6) Run koha qa test tools

NOTE: While this works, I'd be much happier with a refactor
      as it would also speed up the report. See comment #5.

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Brendan A Gallagher <brendan@bywatersolutions.com>